Rhodia Chimie

Rhone-poulenc Chimie

Frederic Robin

Michel Spagnol

Francois Mathey

Francois Mercier

Virginie Mouries

A process for separating the (d/l) and (meso) diastereoisomers of bis-&lsqb;1-phospha-2,3-diphenyl-4,5-dimethylnorbornadiene&rsqb; comprising converting the mixture of diastereoisomers of bis-&lsqb;1-phospha-2,3-diphenyl-4,5-dimethylnorbornadiene&rsqb; to a mixture of the corresponding diastereoisomers of diphosphine disulphide or dioxide, then in separating the two diastereoisomers in dioxide or disulphide form.

Method for separating a diphosphine diastereoisomers

6,6&prime;-bis-(1-phosphanorbornadiene) diphosphines, their preparation and their uses

6&prime;,6-bis-(1-phosphanorbornadiene) diphosphines

Asymmetric hydrogenation method of a ketonic compound and derivative

The present invention relates to optically active diphosphines. It is also targeted at their preparation according to a process for the resolution of the racemic mixture of the said phosphines to optically active isomers. The subject of the invention is new optically active bis[1-phospha-2,3-diphenyl-4,5-dimethylnorbornadiene] diphosphines and a process for resolving the racemic bis[1-phospha-2,3-diphenyl-4,5-dimethylnorbornadiene] mixture which comprises reacting it with a palladium or platinum complex as chiral auxiliary in an organic solvent, thus forming diastereoisomer complexes, and then resolving the said optically pure complexes. The invention also relates to new optically active metal complexes comprising the said phosphines and to their use in a process for the preparation of optically active carboxylic acids and/or derivatives according to a process for the hydrogenation of .alpha.,.beta.-unsaturated carboxylic acids and/or derivatives.

Optically active diphosphines, preparation thereof according to a

Growing community of inventors

Montrouge, France

Frederic Robin